Have you noticed a purple haze across the fields right now? If so, you may have wondered, “What kind of flowers are they?”
A purple haze of color stretches across fields not already green with cold-season crops like winter wheat.
Say hello to Purple Dead Nettle (Lamium purpureum), a non-native invasive species that has increased its prevalence in recent years by finding an improved niche in no-till cropland. Purple Dead Nettle, also known as Red Dead Nettle, is native to Asia and Europe. It has been a familiar early spring “weed” in gardens, along roadsides, and in other disturbed ground for decades.
Purple Dead Nettle owes its new-found success to the timing of its compressed growing season. Its tiny seeds germinate during the fall and winter, after crops have been harvested and herbicide application has ended for the season. The plants flower early in the spring and are thus particularly attractive to Honey Bees and other pollinators looking for a source of energy-rich nectar as they ramp up activity after winter lock down. In many cases, Purple Dead Nettle has already completed its flowering cycle and produced seeds before there is any activity in the field to prepare for planting the summer crop. The seeds spend the warmer months in dormancy, avoiding the hazards of modern cultivation that expel most other species of native and non-native plants from the agricultural landscape.
Flowering Purple Dead Nettle as a volunteer cover crop among last year’s corn stubble in a no-till field.Like the flowers of orchids, Purple Hedge Nettle blossoms are described as yoke shaped or bilateral (zygomorphic). Psychedelic experiences are produced only through observation, not by ingestion. A member of the mint family, its edible young leaves and tops have nutritional value, making a unique addition to salads and soups.We call them “weeds”, but what do we know? Purple Dead Nettle, Common Dandelion, and Shepherd’s Purse (Capsella bursa-pastoris), three edible non-native invasive species with similar life cycles seen here flowering along a rural road among fields where intensive farming is practiced. Shepard’s Purse, like many members of the mustard family, is already producing seeds at the bottom of the flower cluster by the time the uppermost buds open for business.In preparation for seeding of a warm-season crop, herbicide is applied on a no-till field to kill Shepherd’s Purse and other cool-season plants. To help prevent sediment and nutrient discharge from lands where high-intensity agriculture is practiced, no-till methods are used to reduce runoff from the areas of bare soil that would otherwise be created by traditional plowing.
While modern farming has eliminated a majority of native plant and animal species from agricultural lands of the lower Susquehanna valley, its crop management practices have simultaneously invited vigorous invasion by a select few non-native species. High-intensity farming devotes its acreage to providing food for a growing population of people—not to providing wildlife habitat. That’s why it’s so important to minimize our impact on non-farm lands throughout the remainder of the watershed. If we continue subdividing, paving, and mowing more and more space, we’ll eventually be living in a polluted semi-arid landscape populated by little else but non-native invasive plants and animals. We can certainly do better than that.
This stream restoration project is currently underway along a one-mile-long segment of Lancaster Conservancy lands along Conewago Creek. The mountain of dirt is one of several stockpiles of legacy sediments removed to reestablish the floodplain’s historic geomorphology. After eroding from cropland during the years prior to soil conservation, legacy sediments accumulated behind mill dams on waterways throughout the lower Susquehanna watershed. After removal of the dams, creeks were left trapped within the sediment-choked bottomlands, incising steep muddy banks as they cut a new path through the former mill ponds. Excavating legacy sediments from these sites eliminates creek banks and allows floodwaters to again spill directly into wetlands along the stream course. With floodplain and wetland functions restored, nutrients are sequestered, high water is infiltrated to recharge aquifers, sediment loads from collapsing banks are eliminated, and much-needed habitat is created for native plants and animals.
To learn more about this project and others, you’ll want to check out the Landstudies website.
At this very moment, your editor is comfortably numb and is, if everything is going according to plans, again having a snake run through the plumbing in his body’s most important muscle. It thus occurs to him how strange it is that with muscles as run down and faulty as his, people at one time asked him to come speak about and display his marvelous mussels. And some, believe it or not, actually took interest in such a thing. If the reader finds this odd, he or she would not be alone. But the peculiarities don’t stop there. The reader may find further bewilderment after being informed that the editor’s mussels are now in the collection of a regional museum where they are preserved for study by qualified persons with scientific proclivities. All of this show and tell was for just one purpose—to raise appreciation and sentiment for our mussels, so that they might be protected.
Click on the “Freshwater Mussels and Clams” tab at the top of this page to see the editor’s mussels, and many others as well. Then maybe you too will want to flex your muscles for our mussels. They really do need, and deserve, our help.
Submersed aquatic plants in streams, lakes, ponds, bays, and estuaries do more than take up nutrients and provide habitat for fish and other organisms, they produce oxygen during photosynthesis. Here we see tapegrass (Vallisneria) in bright sunlight releasing a visible string of oxygen bubbles, an emission known as “pearling”. British chemist, theologian, and philosopher Joseph Priestly (1733-1804), who spent his final decade residing along the Susquehanna in Northumberland, Pennsylvania, isolated oxygen during experiments in 1774 by exposing mercuric oxide to direct sunlight. During the following year, Priestly published his findings in “An Account of Further Discoveries in Air”, describing what he called “dephlogisticated air”, the gas later named oxygen. To observe and record the effects of pure oxygen in the absence of atmospheric air, Priestly first tested it on a mouse, then breathed it himself.
There are two Conewago Creek systems in the Lower Susquehanna River Watershed. One drains the Gettysburg Basin west of the river, mostly in Adams and York Counties, then flows into the Susquehanna at the base of Conewago Falls. The other drains the Gettysburg Basin east of the river, flowing through Triassic redbeds of the Gettysburg Formation and York Haven Diabase before entering Conewago Falls near the south tip of Three Mile Island. Both Conewago Creeks flow through suburbia, farm, and forest. Both have their capacity to support aquatic life impaired and diminished by nutrient and sediment pollution.
This week, some of the many partners engaged in a long-term collaboration to restore the east shore’s Conewago Creek met to have a look at one of the prime indicators of overall stream habitat health—the fishes. Kristen Kyler of the Lower Susquehanna Initiative organized the effort. Portable backpack-mounted electrofishing units and nets were used by crews to capture, identify, and count the native and non-native fishes at sampling locations which have remained constant since prior to the numerous stream improvement projects which began more than ten years ago. Some of the present-day sample sites were first used following Hurricane Agnes in 1972 by Stambaugh and Denoncourt and pre-date any implementation of sediment and nutrient mitigation practices like cover crops, no-till farming, field terracing, stormwater control, nutrient management, wetland restoration, streambank fencing, renewed forested stream buffers, or modernized wastewater treatment plants. By comparing more recent surveys with this baseline data, it may be possible to discern trends in fish populations resulting not only from conservation practices, but from many other variables which may impact the Conewago Creek Warmwater Stream ecosystem in Dauphin, Lancaster, and Lebanon Counties.
So here they are. Enjoy these shocking fish photos.
Matt Kofroth, Watershed Specialist with the Lancaster County Conservation District, operates the electrofishing wand in Conewago Creek while his team members prepare to net and collect momentarily-stunned fish. Three other electrofishing units operated by staff from the Susquehanna River Basin Commission and aided by teams of netters were in action at other sample locations along the Conewago on this day.Really big fish, such as this Common Carp (Cyprinus carpio), were identified, counted, and immediately returned to the water downstream of the advancing electrofishing team. Koi of the garden pond are a familiar variety of Common Carp, a native of Asia.Other fish, such as the Swallowtail Shiner, Redbreast Sunfish (Lepomis auritus), Fallfish, and suckers seen here, were placed in a sorting tank.Fallfish (Semotilus corporalis) are very active and require plenty of dissolved oxygen in the water to survive. Fallfish, Rainbow Trout (Oncorhynchus mykiss), and Smallmouth Bass (Micropterus dolomieu) were quickly identified and removed from the sorting tank for release back into the stream. Other larger, but less active fish, including suckers, quickly followed.Small fish like minnows were removed from the sorting tank for a closer look in a hand-held viewing tank. This Fathead Minnow (Pimephales promelas) was identified, added to the tally sheet, and released back into the Conewago. The Fathead Minnow is not native to the Susquehanna drainage. It is the minnow most frequently sold as bait by vendors.A breeding condition male Bluntnose Minnow (Pimephales notatus).The Cutlips Minnow (Exoglossum maxillingua) is a resident of clear rocky streams. Of the more than 30 species collected during the day, two native species which are classified as intolerant of persisting stream impairment were found: Cutlips Minnow and Swallowtail Shiner.This young River Chub (Nocomis micropogon) is losing its side stripe. It will be at least twice as large at adulthood.The Eastern Blacknose Dace (Rhinichthys atratulus) is found in clear water over pebble and stone substrate..The Longnose Dace (Rhinichthys cataractae) is another species of pebbly rocky streams.A juvenile Golden Shiner (Notemigonus crysoleucas). Adults lack the side stripe and grow to the size of a sunfish.A Swallowtail Shiner (Notropis procne) and a very young White Sucker (Catostomus commersonii) in the upper left of the tank.A Spotfin Shiner (Cyprinella spiloptera).A breeding male Spotfin Shiner. Show-off!The Margined Madtom (Noturus insignis) is a small native catfish of pebbly streams.The Banded Killifish (Fundulus diaphanus) is adept at feeding upon insects, including mosquitos.A young Rock Bass (Ambloplites rupestris). This species was introduced to the Susquehanna and its tributaries.The Greenside Darter (Etheostoma blennioides) is not native to the Susquehanna basin. The species colonized the Conewago Creek (east) from introduced local populations within the last five years.The Tessellated Darter (Etheostoma olmstedi) is a native inhabitant of the Susquehanna and its tributaries.The stars of the day were the American Eels (Anguilla rostrata).After collection, each eel was measured and weighed using a scale and dry bucket. This specimen checked in at 20 inches and one pound before being released.Prior to the construction of large dams, American Eels were plentiful in the Susquehanna and its tributaries, including the Conewago. They’ve since been rarities for more than half a century. Now they’re getting a lift.American Eels serve as an intermediate host for the microscopic parasitic glochidia (larvae) of the Eastern Elliptio (Elliptio complanata), a declining native freshwater mussel of the Lower Susquehanna River Watershed. While feeding on their host (usually in its gills), the glochidia cause little injury and soon drop off to continue growth, often having assured distribution of their species by accepting the free ride. Freshwater mussels are filter feeders and improve water quality. They grow slowly and can live for decades.American Eels are a catadromous species, starting life as tiny glass eels in the saltwater of the Atlantic Ocean, then migrating to tidal brackish marshes and streams (males) or freshwater streams (females) to mature. This 20-incher probably attempted to ascend the Susquehanna as an elver in 2016 or 2017. After hitching a ride with some friendly folks, she bypassed the three largest dams on the lower Susquehanna (Conowingo, Holtwood, and Safe Harbor) and arrived in the Conewago where she may remain and grow for ten years or more. To spawn, a perilous and terminally fatal journey to the Sargasso Sea awaits her. (You may better know the area of the Sargasso Sea as The Bermuda Triangle…a perilous place to travel indeed!)
SOURCES
Normandeau Associates, Inc. and Gomez and Sullivan. 2018. Muddy Run Pumped Storage Project Conowingo Eel Collection Facility FERC Project 2355. Prepared for Exelon.
Stambaugh, Jr., John W., and Robert P. Denoncourt. 1974. A Preliminary Report on the Conewago Creek Faunal Survey, Lancaster County, Pennsylvania. Proceedings of the Pennsylvania Academy of Sciences. 48: 55-60.
